The present invention concerns an air diffuser for a vehicle, in particular for ventilation, heating and/or air conditioning of the passenger compartment.
Air diffuser are known for use in vehicles of various kinds. They allow a entry of fresh air, heated and/or colled air into a vehicle interior. Usually, anticipated air diffusers have an air outlet element with passage ways and which is rotatable around one or several axes. By orienting the air outlet element the direction of the air stream can be selected.
From patent DE 19721831A1 an air diffuser for the interior of a vehicle is known where the air outlet element features a partial area for a diffuse air exit and a partial area for an unrestricted air exit over a larger area, and where the manner of the air exit can be selected by turning the air exit element.
From patent DE 4338099C2 is also known an instrument panel with a large-surface perforated air exit surface covering an airduct on one side, for diffuse air distribution.
Here the large-surface perforated air exit area forms the top side of the instrument panel facing the windshield. The air exit area is connected to an air distributor box which has a perforated ventilation damper for controling the airstream. Additional air supply devices for the vehicle interior which allow diffuse ventilation, are for instance known from patents DE 3908541C2, DE 1530615 and DE 1909519.
Anticipated air outlets are generally adjusted manually. There are however air outlets in the luxury class that are driven by an actuator.
From patent DE 3717676 A1 a vehicle air conditioning unit is known which has a bimetallic tab which effects a commutation at a channel branching, depending on the airstream temperature, the airstream intensity or according to a time function.
A disadvantage of anticipated air outlets for producing a diffuse flow field is the flow field is not adequately diffuse, i.e., that it is still distinguishable as a directed flow field and/or that the constructive expenditure for obtaining the diffuse flow field is relatively high.
Furthermore it is also known from the state of the art, to provide a vehicle seat with ventilation. In the so-called “climate seat” of the BMW 7 vehicles multistage fans are imbedded in the upholstery of seat and back which circulate air from the vehicle interior through the seat upholstery. By means of balance control heat distribution between the seat are and the seatback can be adjusted individually. Here again it is disadvantageous that the constructive expenditure for making such a ventilated seat is relatively high.
The invention is therefore based on the objective to create an improved air outlet for a vehicle, as well an an improved instrument panel, a headliner and interior covering with a ventilating function, as well as a vehicle seat with integrated ventilation.
The objective the invention is based on is being solved with the characteristics of the individual patent claims. According to invention an actuator for the air outflow is used which features a temperature-inducible deformation effect. Furthermore, means are provided for inciting the deformation effect, in order to achieve a desired setting of the airstream.
According to a preferred design of the invention the actuator is in the form of a flexible strip. When for instance a current is applied to the actuator the actuator gets hot and bends so that an air exit opening is unblocked more or less. Alternatively the deformation effect of the actuator is induced by heating the actuator with a controllable radiation source.
According to another preferred design of the invention the actuator is formed for the arching of an interior covering. For this purpose, several adjacent actuators are for inprovided which each featuring a deformation effect in the opposite direction. Through temperature induction of the de formation effect this results in the formation of air exit openings of varying size.
According to another preferred design of the invention the actuators are arranged on a meander-shaped support. The deformation effect causes a deformation of the support which consequently unblocks a air exit opening.
According to another preferred design of the invention the actuator is supported solidly one one side and detachably on an opposite side. The detachable support may for instance be realized with electromagnetic means.
According to another preferred design of the invention each actuator can be controlled separately, or groupd of actuators are formed with the individual groups being each separately controllable.
According to a preferred design of the invention a large-surface air exit area is realized in the area of the instrument panel, the headliner or another interior covering component. For this purpose several actuators are distributed over the air exit area.
According to another preferred design of the invention one or several actuators are provided in a vehicle seat for supplying the airstream through the seat surface.
For the realization of the temperature-inducible deformation effect of the actuator several suitable technologies may be applied. An actuator may for instance be realized by sandwiching materials of different thermal expansion coefficients; when different metallic materials are used, such an arrangement is called a bimetall strip.
According to a preferred design of the invention the temperature-inducible deformation effect is achieved by using materials with a shape-memory effect. Appropriate alloys are also called Shape-Memory-Alloys (SMA). Examples for this are the NiPi- and NiTiPb alloys. Additional shape-memory alloys are known from “Alloys with Shape-Memory”, Dieter Stöckel, Erhard Hornbogen, Expert-Verlag, 1988, ISBN 3-8169-0323-1. Alternatively or additionally conductive synthetic materials as they are known in the field of polyelectronics may be used.
The deformation effect is a reversible effect. For this one may use a one-way effect with an additional mechanic readjusting device. This reversible effect is based on the fact that so-called memory-alloys are considerably less solid in the martensitic state than in the high-temperature phase. It is therefore by heating that the deformation of the actuator into the high-temperature form is achieved, for instance through the supply of an electrical current. After the current is switched off the actuator does not automatically resume its original shape, but it is returned ot its original shape by a force produced by appropriate mechanical means.
Alternatively, a material is used that features a two-way effect. With the two-way effect the material “remembers” both the high-temperature and a low-temperature form. As a special case of the two-way effect one may also use materials featuring an all-round effect.
Use of materials with shape-memory effect for automotive technology is as such known from “Alloys wwith shape-memory”, chapter 3.8.2, page 92 to 94, and notably for fog lights with protective lamella against stones with a nickel-titanium spring as memory element and also for temperature-dependent actuating functions for engines, transmissions and chassis, as for instance for fan clutches of engines, throttling devices of injection pumps as well as for vehicle transmissions with enhanced shifting behavior. From patent CA 2346260A1 one is also familiar with the use of shape-memory alloys for the setting/adjusting of a rearview mirror.